The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Generally, a mechanical thermostat is used to control a temperature of a coolant circulating in an engine, and the mechanical thermostat has a structure in which wax of the mechanical thermostat expands to open a coolant flow path connected to a radiator and to control the temperature of the coolant when the temperature of the coolant increases.
The mechanical thermostat is disposed at a coolant outlet of an engine to control an outlet temperature of the engine or at a coolant inlet of the engine to control an inlet temperature of the engine, wherein the former is referred to as an engine outlet control method and the latter is referred to as an engine inlet control method.
Since the engine outlet control method senses a temperature of a coolant flowing out of the engine and then performs predetermined control, it is possible to prevent the temperature of the coolant from being excessively increased, but since a point for sensing the temperature of the coolant is positioned at the coolant outlet of the engine, accuracy of the control may be degraded.
In contrast, since the engine inlet control method senses the temperature of the coolant at an inlet of the engine, variation of the temperature of the coolant is small and accuracy of the control is high, but the temperature of the outlet of the engine may excessively increase according to output of the engine.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the disclosure and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art.
Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.